Mount Prospect, Illinois 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

243
FXUS63 KLOT 031925
AFDLOT

Area Forecast Discussion
National Weather Service Chicago/Romeoville, IL
225 PM CDT Fri Apr 3 2026

.KEY MESSAGES...

- Scattered thunderstorms tonight with heavy rain/localized
  flooding as well as severe potential, mainly south of I-80.

- A transition toward a quieter, but cooler, pattern is on track
  to arrive Sunday through early next week before milder and
  more active weather returns for the second half of the week.

&&

.DISCUSSION...
Issued at 225 PM CDT Fri Apr 3 2026

Primary forecast concerns are severe and heavy rain potential
through tonight.

A cold front (lake enhanced) is moving across the area now with
northeast winds currently through the I-80 corridor. this front
will continue moving south into the Illinois and Kankakee River
valleys later this afternoon and possibly into the far southern
cwa by early this evening. This will confine the tornado
potential to the far southwest/southern cwa later this afternoon
and this evening, leaving just mainly a limited hail potential
for the rest of the area. Models have been in fair agreement
with convection developing during the late afternoon across west
central IL and then lifting northeast across the metro area
through the evening. Ahead of this potential, at least isolated
thunderstorms are possible across northwest IL with the
activity currently across northeast IL. There may be a brief
lull in the late evening then another round of showers and
thunderstorms are expected overnight, affecting most of the
area. The main threat during this time period will be heavy
rainfall (which is also possible this evening), which may lead
to localized flooding. Given how much rain has already fallen
over recent days, the saturated soils and elevated rivers/
streams, its possible flooding may develop a bit faster if heavy
rain remains over the same areas. Thus the flooding potential
will need to be monitored closely this evening and overnight.

A cold front will move across the area Saturday with showers
likely during the morning until the front actually moves
through, though there remains uncertainty for how widespread the
showers will become as well as the end time. While the bulk of
the heavier showers and remaining thunderstorms should be
exiting the eastern cwa around/after daybreak, only medium
confidence for precip trends/end times Saturday morning.

Westerly winds will steadily increase Saturday morning and may
gust as high as 35 mph in the afternoon/early evening and then
begin to slowly diminish Saturday evening, though it will still
remain breezy/windy Saturday night into Sunday morning. The
gradient begins to weaken Sunday afternoon, which may allow for
a lake breeze, at least into northwest IN Sunday afternoon.

A stronger cold front is expected to move south across the local
area Sunday night, bringing colder temperatures. Generally dry
weather is expected during this time period though a few
flurries are possible. Depending on how cold the airmass
eventually becomes, there could be some lake effect snow
showers/flurries but the potential looks low at this time.

Southerly flow and warmer temps return midweek ahead of another
cold front that may become stationary across the local area
through the end of next week, making for a possible unsettled
pattern to return to the area. cms

&&

.AVIATION /18Z TAFS THROUGH 00Z SUNDAY/...
Issued at 1249 PM CDT Fri Apr 3 2026

Primary forecast concerns include...

Chance of thunderstorms this evening and overnight.
Ifr/lifr cigs tonight/Saturday morning.
Wind shift from southeast to southwest Saturday morning.

Light winds currently are in the process of shifting easterly
with speeds gradually increasing through the afternoon. Gusts
into the lower/mid 20kt range are expected late this afternoon
through the evening and then will diminish overnight and turn
southeasterly. Winds will quickly shift southerly then west/
southwest as low pressure moves across the area. Westerly winds
will gust in the mid/upper 20kt range for much of Saturday.

Showers and scattered thunderstorms are expected to develop west
and south of the terminals late this afternoon and then spread/
lift northeast across the terminals during the evening. As the
models continue to trend in this direction, have changed the
current prob to tempo mention for this time period. Isolated
thunderstorms are possible near RFD late this afternoon and have
included prob mention for this time period. There may be a few
hour break in the late evening or early overnight hours, then
additional showers and scattered thunderstorms are expected
during the overnight hours and have included prob mention for
this potential. Showers may linger past sunrise Saturday morning
with an uncertain end time and some additional shower mention
may be needed through mid/late Saturday morning.

Mvfr cigs are expected to return this afternoon as easterly
winds increase off Lake Michigan though there is uncertainty for
when and how widespread mvfr cigs may become. Cigs will slowly
lower through mvfr this evening and into ifr by late evening and
lifr overnight. Only medium confidence for overall cig trends
and changes are possible with later forecasts. Cigs should
gradually lift back into low mvfr Saturday morning with a brief
period of scattering out possible midday with mvfr cigs expected
much of the day. cms

&&

.LOT WATCHES/WARNINGS/ADVISORIES...
IL...None.
IN...None.
LM...None.

&&

$$

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